A judge handed down a 35-year additional prison sentence to a Wyoming prison inmate for trying to hire the services of a contract killer to kill his mother and stepfather while incarcerated, according to the Associated Press.

Andrew Silicani, 23, received the sentence on four counts of using the mail in his unsuccessful attempt to order the killings, according to Fox News.

Silicani wanted to collect his parents' life insurance and take over their house worth a total of $850,000, according to court records.

The U.S. District Judge Nancy Freudenthal imposed the additional sentence, saying it was heartbreaking that Silicani considered getting his mother murdered in spite of the support she offered when he was suffering from mental health problems, the prosecutor said.

Silicani was serving five to seven years in the state prison for two robbery convictions, including one in which a victim was stabbed. He will serve the 35-year federal sentence after his state term expires in 2018.

Silicani's mother Cheryl Lambert told the judge that the sentencing hearing was "the saddest and most difficult day of her life." She said she loved her son, but she and her husband are afraid that Silicani would attempt to kill them if he's released from the prison, according to CBS-affiliated KGWN.